Antimicrobial activity of bioactive glass associated to Brazilian red and green propolis

Bioactive glasses are a group of surface reactive glass-ceramics and are able to induce the formation of mineralized tissue in vivo, maxillofacial and periodontal repair. In this work we are studied the 58S glass type produced in the UFMG Biomaterials Laboratory using the sol-gel process comprising SiO₂ (46.1 mol%), P₂O₅ (4 mol%) and CaO (26.9 mol%) associated with green propolis originated by Baccharis dracucunlifolia (GP), red propolis originated by Dalbergia ecastophylum (RP) and tetracyclin (TC) and shaped in 6.0mm diameter discs. The antimicrobial susceptibility test for the different discs was conducted according to CLSI (2007) guidelines. 1.0×10⁸ CFU/mL of Enterococcus faecalis, Streptococcus mutans, Staphylococcus aureus were plated on Mueller-Hinton agar. The discs were placed on the agar surface and incubated at 37^oC during 48h. TC standardized discs 30mg, Blanc stelilized discs content 20µL of GP and RP ethanolic extract, bioglass without propolis and TC were used as controls. After incubation, the inhibition zones were measured and reported as mean±standard deviation. Kruskal-Wallis test: p<0.5 was considered significant. All tests were made in triplicate. The results show that RP was more efficient and equal against three microorganisms (22.5±0.0mm) whereas GP showed 15mm (S. aureus), 12mm (E. faecalis), 19mm (S. mutans). The GP and RP extracts had shown similar effectiveness. The bioglass associate with Red Propolis demonstrated to greater antimicrobial activity that observed for tetracyclin and other controls.

Acknowledgments: FAPEMIG – Fundação de Apoio a Pesquisa do Estado de Minas Gerais; CNPq – Conselho Nacional de Desenvolvimento Científico e Tecnológico; CAPES – Coordenação de Aperfeiçoamento de Pessoal de Nível Superior; Pharm. Dra. Sheila Rago Lemos Abreu (Pharmanéctar- Belo Horizonte- Brazil); Coordenação dos Cursos de Pós-Graduação da Faculdade de Odontologia da UFMG.